CVE-2021-20812 Cross-site scripting in Movable Type
Remote attackers can inject arbitrary scripts into the Server Sync settings screen of Movable Type, potentially compromising user sessions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2021-20812?
CVE-2021-20812 is a medium-severity cross-site scripting vulnerability in Six Apart Ltd. Movable Type, published on 26 Aug 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Cross-site scripting vulnerability in Setting screen of Server Sync of Movable Type (Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series) and Movable Type Premium Advanced 1.44 and earlier) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.
Weakness: CWE-79
Which versions are affected by CVE-2021-20812?
It affects 1 product.
Products include Sixapart Movable Type.
How do I fix CVE-2021-20812?
No fix has been published for CVE-2021-20812 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2021-20812 being exploited?
There is no known exploitation of CVE-2021-20812 in the wild and no public exploit code.
Other vulnerabilities in Six Apart Ltd. Movable Type
Sources
Also known as GHSA-2554-pph3-4jmx.